Unofficial news and tips about Google

September 29, 2009

Google Docs OCR

Google Docs API tests a new feature that lets you perform OCR (optical character recognition) on an image. There's a live demo that illustrates this feature: you can upload a high-resolution JPG, GIF, or PNG image that has less than 10 MB and Google Docs extracts the text and converts it into a new document. Google mentions that "the operation can currently take up to 40 seconds" and a small test showed that the service is not yet reliable: it's slow and it frequently returns errors.

The results are far from perfect and you'll find many errors, but the service is free and it's constantly improving. Here's the result of the OCR for this scanned document:

There aren't many free OCR services available, so an OCR service provided by Google would be very popular. ABBYY FineReader Online is one of the best online OCR services, but the free version is limited to 10 pages a day.

Google sponsors the development of an open-source OCR software called OCRopus, but it's not clear if the online service provided by Google Docs uses OCRopus.

25 comments:

@ebboodah — yup, then can send hard words to users od reCaptcha to get amazing accuracy. And soon after that, cybercriminals will invent API to send reCaptcha images to Google Docs OCR for great accuracy of spamming. Perpetuum mobile. :D

I just tested it on some pictures. In some cases, I need to resize *2 the image, to be recognized, but it's awesome to be able to use OCR online !Don't forget OCR is very complex technology, so, be patient !

it would be so kind of you if you could further in your endeavour and make Google Docs OCR work for Hebrew and Arabic. Perhaps, Cyrillic too. Certainly, people who read Chinese, Japanese or Hindi have similar levels of enthusiasm too.

This is great news, as I have a lot of books I wish to scan. Contrary to people who love collecting books on shelves but not reading them, I love reading books but not keeping them. Printed books are real heavy stuffs and inconvenient to move around with. Printed books also do not lend themselves willingly towards searching their contents - very bad feature.

I want to be able to read my stuffs anywhere I am in the world. I would scan the books, recycle the paper, but keep the covers in a trunk in an obscure corner of the cellar as proof of my ownership of the books.

BTW, what's the meaning of "performant"? I am afraid the frequent appearance of this word is about to make it join the list of annoying words like "obligated" that have replaced "obliged", "percentage points" instead of "percent" or "presumptive candidate" instead of "presumed candidate" as real words.

Actually, "percentage points" is an important concept, with a different meaning from "percents". For example, let's say that in one year, unemployment was 10%, and in the next year it rose to 11%. You might say that "Unemployment rose by 1 percentage point", or that "Unemployment rose by 10 percent" (because 1% is 10% of 10%; the number of unemployed rose by 10%). It would be confusing and *wrong* to say that "Unemployment rose by 1 percent". This is why the term "percentage point" is needed.

I think that they are using neither Ocropus nor Tesseract. When i gave the same image to Google OCR, Tesseract, and Ocropus, I noticed that Google OCR provided better results than Tesseract, and Tesseract provided much better results than Ocropus, although Ocropus uses Tesseract as the recognition engine....strange!

I nearly tried all free online OCR services. All of them give more or less the same quality. I really like i2OCR because it provides a balance between accuracy and usability.http://www.sciweavers.org/free-online-ocr

Finally, the secret sauce is DPI. The more DPI, the better the quality of recognition.

Well, I just tried Google's OCR and it was on pants at b/w 600dpi. Junk character"5 and no formatting. This may have been down to the font (bold Tahoma, don't ask me why, some people just have no sense of style). However, tried the same document with onlineocr.net, and got much better results.